Kirk is, frankly, surprised that McCoy has ever had a girlfriend at all, let alone a wife. The man is absolutely impossible to pick up. Jim should know, he's tried. Well okay, to be fair, he'd only tried the once, and it wasn't long after they'd met. McCoy had been nice about rejecting him (in a totally awkward way), so Jim had laughed it off and pretty much forgotten about it. There were plenty of other fish at the Academy...cadets in the sea...whatever.
But the thing is, he pays attention when they're out together, and it hasn't escaped his notice that McCoy gets hit on. A lot. When they go drinking - which, granted, isn't that often - there are always a couple offers. McCoy usually shrugs those off by throwing an arm around Jim's shoulder and buying them both another drink. And yes, Jim realizes that he's basically being used as a cockblock, but hey, at least he's getting free drinks out of it. It kind of makes sense to Jim. McCoy obviously isn't the one night stand type, so turning down offers in bars is none too surprising.
And then there are Bones' colleagues, classmates. Jim doesn't see them terribly often, but he's come to meet Bones after class or a hospital shift on a number of occasions, and once in awhile one of them will be asking him out. He always gives them a "no thanks, I'm busy that night" and comes striding over to Jim, looking relieved to see him. Even that, Jim can understand, because it's just smart not to get involved with someone you're basically competing for jobs with.
But then there are the girls in McCoy's dorm. It seems like any time Jim's over visiting him, at least one will come by to flirt or ask McCoy if he wants to study with her. It's a line - one Jim knows well - but McCoy plays oblivious, saying he prefers to study on his own or that he's all caught up with whatever subject they're discussing. And Jim knows he really is just playing oblivious, because he always makes some remark about being too old for that kind of shit. Jim's pretty sure that excuse is bullshit.
What bothers Jim about the whole thing is that he can't keep himself from thinking about it. There has to be a reason that no one has been successful with Bones, and he damn well wants to know what it is, what it would take to win Bones over. He's never been good at resisting a challenge, and this is no exception.
So he starts off small, asking Bones to tell him stories from his pre-Academy days. They're interesting, painting a portrait of a mostly-happy family man working as a country doctor. Bones skirts talking about the ex-wife (who he refuses to call anything else; Jim still doesn't know her name) in detail, but he's got a million and one things to say about his daughter. And as much as Jim likes to hear about all that, it doesn't ultimately help him with his goal.
He moves on to simply asking Bones about the why whenever he turns anyone down. He gets answers ranging from "I don't do casual sex" to "he really wasn't my type" to "she never fucking stops talking about warp theory". Some of it's helpful, but mostly in the way of telling him what not to do, which wasn't really the problem in the first place.
One day, he gets fed up enough that he just lays it out plainly. "How come you always turn everyone down?"
McCoy merely raises an eyebrow.
"Every time you get a proposition or someone asks you on a date, you always say no, and I can't figure out why." Jim knows he sounds frustrated, but he is, and he's not gonna try to hide it.
"They're just not right for me. And it's not like I'm really looking, anyway. Ended badly enough with the ex-wife that I'm not sure I really want another go."
That sounds...really fucking depressing, to Jim's mind. And also kind of impossible. Then again, Bones has always been kind of impossible, but Jim has managed to get in far enough to be his friend. He can get more from Bones; he's sure of it.
The first step is to stop sleeping around so much. It isn't exactly easy, given that he's used to pretty regular sex, but he can do it; he has his right hand, after all.
The second step (although he's less sure of this one) is to spend more time with Bones, preferably in a more romantic setting than the cafeteria or a bar. It really isn't that difficult, convincing Bones that they should go out to eat or to a movie or something. Hell, he even tries the studying line that failed for so many others, but that just ends up, well, with them studying more often. The problem is that he just can't figure out how to move it beyond mere hanging out without getting shot down.
And of course, he doesn't let himself look too closely at his reasons for doing any of this in the first place. Somewhere along the line it's become something more than just a challenge (if it ever was that), but Jim isn't sure he wants to know why he's still so hung up on this. So he just keeps trying.
The funny thing is that Jim stumbles upon the answer without even meaning to or realizing it. He's sitting in Bones' room by himself one day, waiting for Bones to get back from his shift at the hospital when a transmission comes through. And oh shit, that would be Joanna; Bones had said something about her mother letting her call today after his shift was over, which of course means that Bones is running late.
Jim debates for a moment before accepting the transmission, afraid that if Joanna has to wait too long, the ex-wife might just end it before Bones even gets back (yeah, that was one of the few ex-wife stories Jim had gotten, and he hadn't liked it one bit).
"Hi, sweetheart, remember me?" he asks when Joanna's smiling face pops up on the screen.
"Jim!" She obviously does remember him, although they've only spoken twice before.
Jim smiles back at her. "Yeah. How are you doing, kiddo?"
They continue talking for the next ten minutes or so, and Jim doesn't even notice when Bones gets back and comes up behind him until Joanna lets out a loud "Daddy!", and then he moves out of the way to let the two of them talk. He lies on Bones' bed, smiling faintly as he listens to them, both sounding happy.
When Bones finally shuts the comm link, he comes over and sits next to Jim on the bed, rousing him from the light doze he'd apparently fallen into. There's a look in his eyes that Jim doesn't think he's ever seen before, and then Bones is leaning down and pressing his lips to Jim's in a gentle kiss. He pulls away before Jim can get with the program enough to really kiss back, but there's a soft smile on his face.
"What was that for?"
"For being there when I needed you."
Jim can't help the grin that crosses his face, and then he's reaching up and pulling an all-too-willing Bones down for another kiss.
Later, when they're lying in bed, naked and basking in the afterglow of some truly stupendous sex, Jim can't help but let out what he's been thinking for so long. "Wasn't sure I'd ever see anyone get past your defenses enough to get you in bed."
Bones chuckled. "Kid, you're the only one who ever had a chance. Only one stubborn enough to put up with me for long enough to get there."
That's really not what Jim was expecting, and it makes his heart clench, but in a good way. "That so? You sure you're not gonna dump me for the next stubborn bastard who comes along?" It comes out flippantly, but Jim is fairly certain that Bones knows it's a serious question, anyway.
"I doubt I could find someone as stubborn as you if I had a hundred lives to live."
It's kind of a double-edged sword, being that stubborn, and Jim knows it, but he also knows what Bones is saying. And maybe, just maybe, they've been headed this way all along. Two stubborn bastards, brought together because neither is willing to give up on the other. Somehow, it sounds right.